JP3520815B2 - Die bonding method for pressure sensor chip - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for die bonding pressure sensor chip by which adherence between a pressure sensor chip and a body block can be improved, by easily uniformly applying an adhesive and performance deterioration or variation of a pressure sensor caused by the adhered state between the chip and block can be prevented. SOLUTION: In a method for die bonding pressure sensor chip in which a pressure sensor chip 1 is adhered to a body block 2 with an adhesive 3, the adhesive 3 is transferred to the adhesive surface 2b of the body block 2 by using an adhesive transfer pin 8 having a flat sharp end and, after the adhesive 3 closing the pressure introducing hole 2a of the adhesive surface 2b is removed by blowing air into the hole 2a, the pressure sensor chip 1 is mounted on and adhered to the adhesive surface 2b.

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for die-bonding a pressure sensor chip (a differential pressure type semiconductor pressure sensor chip) to be mounted on a package or the like (body block). It is. FIG. 4 is a sectional view of a pressure sensor. The pressure sensor chip 1 is mounted on a body block 2, and both are bonded by an adhesive 3. The adhesive 3 is applied over a portion corresponding to the outer periphery of the bonding surface of the pressure sensor chip 1. The measured pressure is applied to the silicon diaphragm 1a of the pressure sensor chip 1 through a pressure introduction hole 2a provided in the body block 2, and an electric signal corresponding to the applied pressure is transmitted from the pressure sensor chip 1 to the bonding wire. 4 to the lead frame 5. FIG. 5 schematically shows a procedure for mounting the pressure sensor chip 1 on the body block 2. First, the adhesive 3 is applied to the bonding surface 2b (die attaching position) on the body block 2 side by the dispenser nozzle 6 (a). The adhesive 3 is applied around the pressure introducing hole 2a, and then the collet 7 holding the pressure sensor chip 1 is hung down on the bonding surface 2b (b), and the pressure sensor chip 1 is mounted inside the body block 2 and bonded. The two are adhered by the agent 3 (c). [0006] As a method of applying the adhesive by the dispenser nozzle 6, there is a method as shown in FIG. 6. FIG. 6A shows a method of applying the adhesive by moving the dispenser nozzle 6 in a substantially circular shape around the pressure introducing hole 2a. Also, FIG.
This is a method of applying a multi-point coating around the pressure introducing hole 2a. [0005] However, FIG.
In the application method as in (a), it is very difficult to continuously apply the adhesive 3 in a uniform thickness, and the amount of the adhesive 3 becomes small and faint at the start of the application, and the adhesive 3 at the end of the application. It tends to be over applied due to dripping. If the adhesive 3 cannot be applied uniformly, the adhesiveness of the pressure sensor chip 1 will be deteriorated, the applied pressure will leak from the bonding surface, and the measurement accuracy will be degraded, the breakdown voltage will be reduced, and the offset voltage will vary. Become. In addition, since the pressure sensor chip 1 is mounted obliquely, a connection failure of the bonding wire 4 is caused. In the multi-point application method as shown in FIG. 6B, the adhesive 3 spreads when the pressure sensor chip 1 is mounted, and the points are connected to each other, so that an application state equivalent to continuous application is obtained.
However, this action depends on the viscosity of the adhesive 3 and the amount of application at each point, and it is difficult to make the thickness of the adhesive 3 uniform even in this method. In addition, there is a problem that it takes time to apply at many points. SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has as its object to easily and uniformly apply an adhesive, to improve the adhesion between a pressure sensor chip and a body block, and to improve the adhesion state. It is an object of the present invention to provide a pressure sensor chip die-bonding method for preventing performance degradation and variation of a pressure sensor. [0008] To achieve the above object,
According to a first aspect of the present invention, in a die bonding method of a pressure sensor chip for bonding a pressure sensor chip and a body block on which the pressure sensor chip is mounted with an adhesive, the pressure sensor chip is provided on the bonding surface on the body block side. In the pressure introducing hole for introducing pressure to the pressure sensor chip, an object having the same size or slightly larger than the pressure introducing hole is installed,
The adhesive is transferred to the adhesive surface using an adhesive transfer pin having a flat pointed tip, and air is injected into the pressure introducing hole to remove the object and the adhesive blocking the pressure introducing hole. The pressure sensor chip is mounted on the bonding surface and bonded. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A method for die-bonding a pressure sensor chip according to a reference example and an embodiment of the present invention will be described below with reference to FIGS. FIG. 1 is a view showing a step of applying an adhesive 3 to an adhesive surface 2b on the body block 2 side as a first reference example of the present invention. The adhesive 3 is generally a silicone paste, but is not particularly limited here. The surface of the adhesive 3 put in the paste tank 9 is smoothed by the squeegee 10 and the thickness thereof is controlled to be constant. An adhesive transfer pin 8 having a flat tip is hung down on the surface of the adhesive 3 to adhere the adhesive 3 (a). Next, the adhesive transfer pin 8 to which the adhesive 3 has been attached is inserted into the pressure sensor chip 1 mounting portion of the body block 2, and the adhesive 3 is transferred onto the bonding surface 2b ((b), (c)). . At this time, the adhesive 3 is in a state of closing the pressure introducing hole 2a of the body block 2 (c). Next, air is injected into the pressure introducing hole 2a from the outside (the side opposite to the bonding surface 2b) to remove the adhesive 3 on the pressure introducing hole 2a ((c),
(D)). This achieves a state in which the adhesive 3 is uniformly applied to the adhesive surface 2b around the pressure introducing hole 2a. Here, the pressure sensor chip 1 is mounted and bonded to the body block 2. This step is shown in FIG.
According to (c). The adhesive transfer pin 8 having a flat pointed tip as described above.
As a result, the adhesive 3 is transferred to the adhesive surface 2b of the body block 2 and only the adhesive 3 in the pressure introducing hole 2a is removed by air, so that the state in which the adhesive 3 is easily and uniformly applied is improved. Realizable and highly reliable pressure sensor chip 1
This has the effect that die bonding can be performed. FIG. 2 is a view showing a step of applying the adhesive 3 to the bonding surface 2b of the body block 2 as one embodiment of the present invention. The steps are the same as in the first reference example ,
Before the adhesive 3 is transferred to the bonding surface 2b by the adhesive transfer pin 8, the spherical object 11 having the same diameter as or slightly larger than the diameter of the pressure introducing hole 2a is placed in the pressure introducing hole 2a on the bonding surface 2b side. Install in position. Next, the adhesive transfer pin 8 to which the adhesive 3 has been attached is inserted into the pressure sensor chip 1 mounting portion of the body block 2, and the adhesive 3 is transferred onto the bonding surface 2b ((b), (c)). . Thus, the adhesive 3 covers the bonding surface 2b including the spherical object 11 (c). Next, air is injected into the pressure introducing hole 2a from the outside (the side opposite to the bonding surface 2b) to remove the adhesive 3 in the pressure introducing hole 2a together with the spherical object 11 ((c),
(D)). This achieves a state in which the adhesive 3 is uniformly applied to the adhesive surface 2b around the pressure introducing hole 2a. Here, the pressure sensor chip 1 is mounted and bonded to the body block 2. This step is shown in FIG.
According to (c). Thus, the spherical object 1 is inserted into the pressure introducing hole 2a.
After installation, the adhesive 3 is transferred to the adhesive surface 2b of the body block 2 by the adhesive transfer pin 8 having a flat tip, and the adhesive 3 in the pressure introducing hole 2a is removed together with the spherical object 11 by air. As a result, in addition to the effect of the first reference example , the intrusion of the adhesive 3 into the pressure introducing hole 2a is prevented, and the adhesive 3 is further removed along the outer peripheral shape of the spherical object 11, thereby further improving the effect. This produces an effect that a ring-shaped coating state that is shaped and highly uniform can be realized. FIG. 3 is a view showing a step of applying an adhesive 3 to an adhesive surface 2b on the body block 2 side as a second reference example of the present invention. The steps are the same as in the first reference example ,
In this method, air is injected from the side of the bonding surface 2b. The function and effect are the same as in the first reference example . [0015] [0016] As described above, according to the present invention, in the first aspect of the present invention of the present invention, prior to transferring the adhesive to the bonding surface by adhesive transfer pins, the same size as the pressure introducing hole Alternatively, a slightly large object was placed at the position of the pressure introduction hole on the bonding surface side, so that the pressure sensor chip and the body block
Improvement of adhesion and performance degradation of pressure sensor due to adhesion condition
Bonding of Pressure Sensor Chip to Prevent Pressure and Variation
In addition, it is possible to prevent the adhesive from entering the pressure introducing hole and to achieve a more shaped and uniform ring-shaped application state.

It is a diagram showing an adhesive application step of the pressure sensor chip die bonding process of a first reference example of the BRIEF DESCRIPTION OF THE DRAWINGS [Figure 1] present invention. 2 is a diagram showing an adhesive application step of the pressure sensor chip die bonding method according to an embodiment of the present invention. FIG. 3 is a view showing an adhesive application step in a die bonding method for a pressure sensor chip according to a second reference example of the present invention. FIG. 4 is a sectional view of a pressure sensor. FIG. 5 is a diagram showing steps of a conventional die bonding method for a pressure sensor chip. FIG. 6 is a view showing a conventional adhesive application state. [Description of Signs] 1 Pressure sensor chip 2 Body block 2a Pressure introduction hole 2b Adhesive surface 3 Adhesive 6 Dispenser nozzle 8 Adhesive transfer pin 9 Paste tank 11 Spherical object

Continuation of the front page (72) Inventor Hiroshi Saito 1048 Kadoma Kadoma, Osaka Prefecture Matsushita Electric Works Co., Ltd. Kaihei 11-135525 (JP, A) (58) Field surveyed (Int. Cl. ⁷ , DB name) H01L 21/52

Claims (1)

(57) Claims 1. In a pressure sensor chip die-bonding method for bonding a pressure sensor chip and a body block on which the pressure sensor chip is mounted with an adhesive, the bonding surface on the body block side is provided. An object having the same size or a slightly larger size as the pressure introducing hole is installed in the pressure introducing hole for introducing pressure to the provided pressure sensor chip, and an adhesive transfer pin having a flat pointed tip is used on the adhesive surface. Transferring the adhesive, injecting air into the pressure introducing hole, removing the object and the adhesive blocking the pressure introducing hole, mounting the pressure sensor chip on the adhesive surface, and bonding. And a die bonding method for a pressure sensor chip.